• JSTS:Journal of Semiconductor Technology and Science
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• v.8 no.3
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• pp.200-209
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• 2008

This paper describes bandwidth linearization techniques in phase-locked loop (PLL) design for common-clock serial link applications. Utilizing a continuously tunable single-input dual-path LC VCO and a constant-gain phase detector, a proposed architecture is well suited to implementing PLLs that must be compliant with standards that specify minimum and maximum allowable bandwidths such as PCI Express Gen2 or FB-DIMM applications. A prototype 4.75 to 6.1-GHz PLL is implemented in 90-nm CMOS. Measurement results show that the PLL bandwidth and random jitter (RJ) variations are well regulated and that the use of a differentially controlled dual-path VCO is important for deterministic jitter (DJ) performance.

• Journal of Environmental Science International
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• v.30 no.5
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• pp.407-412
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• 2021

This study aims to present basic data on long-term sexual effects of Savory (Satureja hortensis) by analyzing its zinc and V.B3 contents. These contents result in the activation of sexual functions induced by the blood concentration of sex hormones, thus improving menopauale symptoms. Results were obtained on August 20, 2020 after experimenting with 100 g of the herb from six indoor (green-house) experimental plots. The V.B3 results were analyzed using 100 g of Savory planted in open soil. Zinc had the highest values at 2.161 mg from the bed soil compounded with sapolite and poultry manure in the indoor condition and 2.077 mg from bed soil mixed with clay in the outdoor condition. The presence of V.B3 in Savory was also confirmed. Further research should be conducted on the interactions between Savory and other herbs.

• Journal of the Korea Concrete Institute
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• v.22 no.5
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• pp.685-694
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• 2010

As a eco-friendly material, Hwangtoh (red clay) has been studied for complete or partial replacement of portland cement. Most of existing studies focused on the material properties of the Hwangtoh concrete including the compressive strength, drying shringkage, and creep. In the present study, the shear strength of the beams made with the Hwangtoh concrete was tested. Further, bond strength of tension re-bars embedded in the Hwangtoh concrete was tested. One of the concrete tested consisted of activated Hwangtoh replacing 20% of the cement. The other consisted 100% activated. Hwangtoh replacing all the cement. The beam specimens were tested under two point static loading. The test result showed that the shear strength of activated Hwangtoh concrete beams replacing 20% and 100% of cement was equivalent to that of the ordinary portland cement concrete beam. However, the bond strength of activated Hwangtoh concrete replacing 100% of the cement was less than that of the ordinary portland cement concrete.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.5
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• pp.43-51
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• 2004

Recently, the importance of choosing correct pavement materials has been increasing in urban spaces and streets. Much research regarding the pavement theory and construction method have been conducted, but analysis in terms of human psychological character has not yet been performed. The purpose of this study is to investigate the psychological characters to 12 pavement materials, that are commonly used in our urban spaces and streets. The results of the psychological character for each pavement material can be summarized as follows: 1. The psychological characters to each pavement material were as follows: ① Clay embodies a natural, traditional, soft and intimate psychological character; ② Pebble stone has a natural, hard, cool and intimate psychological character; ③ Turf grass incorporates an intimate and soft psychological character; ④ Ceramic brick has an artificial and hard psychological character; ⑤ Tile pavement has a modern, artificial, hard and cool psychological character; ⑥ Water permeable concrete has a modern and artificial psychological character; ⑦ Flag stone has a natural psychological character; ⑧ Granite has a modern and artificial psychological character; ⑨ Portland concrete has an artificial and hard psychological character; ⑩ Small compacted brick has an artificial, dynamic and modern psychological character; ⑪ Wood block pavement has a natural and traditional psychological character; ⑫ Asphalt concrete pavement has a modern, hard and artificial character. 2. On the results of the cluster analysis regarding psychological indexes for 12 pavement materials, pavement materials were categorized in 3 clusters. Among them, one cluster was mainly used as the most popular pavement material in our urban spaces and streets. From this point of view, psychological character for pavement material in our urban spaces and streets was not as various as we expected. 3. In conclusion, the proper selection of pavement materials was very important and the factors affecting the human psychological character should be considered in the design of urban spaces and streets.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.3
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• pp.28-37
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• 2016

Through the research and analysis on the hydrological environment and soil environment of habitats through documentary and field studies over 14 habitats of Euryale ferox Salisb. within Jeollabukdo, with the objective of acquiring the basic data for forming an environment based on plantation of reservoirs that are composed with Euryale ferox, the following results were obtained. As a result of analyzing the construction period of the habitats of Euryale ferox from a total of 14 places, the average period of duration after construction of all subject reservoirs appeared to be 71.8 years. Moreover, when examining the relationship between the age of reservoirs and eutrophication, it could be judged that at least the eutrophication of subsoil and water environment is not an obstacle to the growth of Euryale ferox grows in habitats that have a reservoir age of approximately 70 years or more. As a result of analyzing the gardening of soil sediment of the Euryale ferox habitats, the component ingredients appeared to be composed of 80.2% of clay, 16.7% of silt and 3.1% of sand, and the soil class pursuant to such was classified as 'heavy clay'. The organic matter contents of soil sediment appeared to be an average of 36g/kg, and there appeared to be no noticeable difference between the habitats and non-habitats of Euryale ferox. The water quality environment of Euryale ferox habitat appeared to be pH 6.5~7.9, concentration of dissolved oxygen to be $1.8{\sim}8.8mg/{\ell}$, concentration of COD to be $6.8{\sim}74mg/{\ell}$, floating materials to be $2.0{\sim}213mg/{\ell}$, total nitrogen to be $0.422{\sim}10.723mg/{\ell}$, and phosphate to be $0.003{\sim}0.126mg/{\ell}$. The average DO concentration of Aedang Reservoir at Jeongeup, Daejeong Reservoir at Imsil, and Myeongdeokji at Gimje with high vitality and green coverage ratio of Euryale ferox appeared to be $3.5mg/{\ell}$, total nitrogen to be $1.33mg/{\ell}$, and concentration of phosphorus-phosphate to be $0.061mg/{\ell}$. When comparing such with the entire average value, the DO and total nitrogen concentration appeared to be rather low, and the phosphorus-phosphate concentration appeared to be higher by two times or more, thus, an in-depth study on the correlation of the vitality of Euryale ferox Salisb. and concentration of phosphorate-phosphorus will be needed in the future.

• Journal of Ecology and Environment
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• v.32 no.2
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• pp.115-121
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• 2009

In order to elucidate the mechanisms affecting plant distributions in the reclaimed dredging area in the Gwangyang steelworks, in the Gwangyang Bay, Korea, we examined soil characteristics and plant distributions in four study sites and a control site in the study area. Desalination occurring along a gradient with increasing elevation, resulting in decrease of soil pH, EC, P, K, Cl, Ca, Mg, and salt and an increase in soil T-N, silt, clay contents. From site 1 (the lowest-elevation site) to site 5 (the highest-elevation site), halophytes decreased in abundance and nonhalophytes increased. The dominant species in each site were: Phragmites communis, Limonium tetragonum, and 12 additional species at site 1, Carex pumila, Suaeda japonica, and 15 additional species at site 2, Spergularia marina, Scirpus planiculmis, and 22 additional species at site 3, Miscantus sinensis, Lespedeza bicolor, and 26 additional species at site 4 and Pinus thunberii, Rhododendron mucronulatum, and 39 additional species at site 5, which resembled a naturally-occurring P. thinbergii community. Cluster analysis of the vegetation data matrix grouped the 35 plots into 5 major groups, and cluster analysis using the soil environment data matrix revealed 4 major groups. CCA of the floristic and environmental data matrix showed a positive relationship of SAR, EC, Na, Cl, and Ca, which are related to salt, in the $1^{st}$ axis and $2^{nd}$ axis, but negative relationships for altitude, organic contents, silt, and clay contents. Notably, plant species in the reclaimed dredging area that were separated along the $1^{st}$ axis showed strong relationships with factors that related to salt. Long-term exposure to natural rainfall in the reclaimed dredging area changed the soil characteristics, such as salinity. This change in soil characteristics might alter the SAR, which affects plant survival strategies in a given habitat. These results strongly indicated that factors related to salt and elevation play important roles in determining the overall plant distribution in the reclaimed dredging area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6504-6513
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• 2013

The result can be summarized as follows. First, the following periodically changing characteristics were examined:roof form(gambrel/hipped-flat-gable), structure of roof and wall(wood-framed-cement masonry-RC-Light iron framed), roof material(thatched-tiled-slate-cement/steel sheet-asphalt/sandwich panel/mortar water-proofing), wall material(clay plaster/lime plastered-dressing tile/bricks-painting on the cement plastering-native stone dressing/siding/tile), fence material(masonry of stone and cement bricks), and courtyard materials(clay and concrete). Secondly, the regionally changing characteristics of those elements, rural housing structure, roof form, roof structure material, wall finishing material, fence and courtyard material in the outer space, differed according to the location of rural housing, i.e.north, middle, south region. The changing characteristics of both the roof structure and wall structure are similar to those of the three regions.

• KIEAE Journal
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• v.14 no.3
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• pp.105-109
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• 2014

The recent rising living standards, environment-friendly, well-being and health aspects of life in the basic gratification, as well as the desire for a pleasant environment emotionally environmentally friendly way of external space or industrial interest in the indoor environment, the manifestation. In particular, the biggest problem of the indoor environment has been emerged as a Sick House Syndrome indoor space that is provided to the building materials, and the impact on the domestic and the indoor environment, and clean the house in a health standards are specified as laws. The performance rating and the various materials to create environmentally-friendly standards for building materials. The more detail, Porous clay material, toxic substances released by applying the high humidity and the water itself, and to absorb the moisture, if the emissions, without a separate device, to maintain a comfortable indoor environment and at the same time, one of the causes of Sick House Syndrome breaking down harmful substances to absorb a comfortable indoor environment to maintain an environmentally-friendly building interior material studies. It is aimed at the development to multi-functional high performance eco-friendly construction materials, rather than through one feature performance, identify key features for national and international eco-friendly building materials can exert Water Vapour Adsorption raw, decomposed materials for the application and selection.

• Journal of the Korean Geotechnical Society
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• v.22 no.11
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• pp.37-45
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• 2006

Bender elements, composed of thin piezo-ceramics and elastic shims, have been used to measure shear wave velocities of specimens in laboratories. In a preliminary stage of their field applications, an in-house research of optimizing suitable bender elements and their geometrical arrangement has been carried out in a barrel of kaolinite-water mixture. Two types of measurement configuration, similar to cross-hole and in-hole seismic testing, have been implemented. prototype instrumented rods were penetrated into a soft clay layer in the west coast and excellent shear waves were recorded. Development of penetration device (mandrel) and associated instrumented rods are in progress for deeper investigation.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.4
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• pp.73-85
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• 1991

Rhododendron mucronulatum for. albiflorum, native species is a shrub that has white flowers on May to June, and rare species endangered by people's rash digging or cutting. But its physiological ecological characteristics and propagation method are not being known at all. Therefore, this study was executed to utilize this species as the planting material for landscaping by analysing its habitat environment and growth form, and also experimenting its seed and vegetative propagation, and it field culture and utilization. The results are as follows; 1. The elevation, gradient and direction of this species were 295-1,350m, 10-36$^{\circ}$, northwest respectively. It was found that the species is shade-liking plant that grows under forest cover of average 51.33%. 2. The soil pH and water content of its habitat were 5.4, 25.41% respectively. The organic matter content was 6.29% that was higher than 3.2%, the average organic matter content of forest soil in Korea. 3. Representative plant community within which this species was living was Quercus mongolica community, and its main neighboring species were Lindea obtusiloba, Fraxinus sieboldiana, Rhus trichocarpa, Rhododendron Schlippenbachii, Rododendron mucronulatum. 4. The leaf length and width of this species were 39.18mm, 12.60mm respectively. This result showed that generally its leaf size was larger than that of R. micranthum, R. yedoense var. poukhanense and R. mucronulatum var. ciliatum and smaller than that of R. mucronulatum and R. schlippenbachii. 5. The whole size of its pollen was, as 59${\times}$61$\mu\textrm{m}$, the largest of plants of Rhododendron family including R. mucronulatum and R. mucronulatum var. ciliatum. 6. The result of seed germination experiment at intervals of 5$^{\circ}C$ from 15$^{\circ}C$ to 30$^{\circ}C$ presented the highest germination rate of 94.7% at 20$^{\circ}C$ numerically, but high percent germination at all temperature levels without significant difference. And the seed of this plant proved to be sun-liking seed at requiring dormancy in germination. 7. Through seed germination experiment by treatment of growth regulators such as GA. Thiourea and Kinetin under dark condition, it was found that the effect of GA treatment on germination increase and acceleration was the highest. 8. In greenwood cutting, rooted rate by treatment of various concentration of IBA and NAA on clay and vermiculite bed was not wholly high, but 100ppm plots of both IBA and NAA of clay bed showed relatively good rooted rate. 9. As result of field culture experiment for finding out optimum growth temperature and light intensity, growth conditions such as height, number of leaves, fresh weight and chlorophyll contents were the best at night/day temperature of 20/25$^{\circ}C$ and under 1/2sun. Also, the photosynthetic rate was the highest at 25$^{\circ}C$. Accordingly, it was found that optimum temperature and light intensity for growth of this plant are 25$^{\circ}C$ (day temperature), 50% of natural light respectively.